Ricoh Gestetner 5428C, Service Manual

Page: 109 / 152

31 October 2001 MASTER FEED
6-19
Detailed
Descriptions
6.5.2 MASTER FEED MECHANISM
Mechanism
Master feed motor [A] (stepper motor)
↓
Gears [B]
↓
Platen roller [C], master feed roller [D]
↓
Feeds the master (The thermal head makes an image on the master.)
Procedure
1. After the old master has been ejected, the drum stops at the master feed
position and the master clamper opens, ready to clamp the new master.
2. When the clamper is open, the tension roller releases and the master is fed to
the clamper on the drum. For details of the tension roller, see the next section.
3. After the clamper closes, the master feed motor feeds the master while the
drum rotates intermittently at 30 rpm. The intermittent rotation keeps a buckle
[F] in the master above the master feed guide to absorb shocks from the
wrapping operation.
4. The tension roller [E] keeps the master under tension. Without this roller, the
master would crease when the drum turns continuously during wrapping
around the drum, so it reduces the master making time.
5. The main motor turns off when the drum is at the master eject position. The
master feed motor continues to feed the master until master making completed.
Then the master feed motor turns off, and cutting is done.
NOTE: Springs press the thermal head against the platen roller. The pressure is
applied when the master set cover, which includes the platen roller, is
closed.
C238D023.WMF
[A]
[B]
[C]
[D]
[E]
[F]